HK1110564A1 - Reclosable cup lid - Google Patents

Abstract

A reclosable cup cover made by polymeric material thermoforming comprises a domed member and a lathy close plate. The thermoformed domed member has a side wall and a top wall, the top wall comprises an upper surface, a lower surface and a drinking hole in the circumference of the top wall. The top wall is also provided with a pair of slideways hanging down from the lower lateral side of the top wall, and a cylindrical hole arranged inward relative to the drinking hole. The lathy close plate comprises oppositely arranged joining edges, an upper surface with a post protruding upward therefrom, and a drinking hole sealing region. When assembly, the domed member and lathy close plate are assembled together to make the oppositely arranged joining edges of the close plate be slidably mounted inthe slideways and generally displace in the radial direction.

Description

Reclosable cup lid

This application claims priority to U.S. patent application Ser. No.60/617123, filed on 8/10/2004, the entire contents of which are incorporated herein by reference.

Technical Field

The present invention relates generally to cup lids and, more particularly, to a dome-type disposable cup lid with a drinking aperture and an underslung elongated closure plate that is movable generally radially between an open position in which the aperture communicates with the interior of the dome and a closed position in which the closure plate covers the aperture to mitigate or substantially prevent spillage.

Background

Considerable variations in the construction of the reclosable cap as a whole can be made by the following: leggett, U.S. patent No.581293 entitled "Can Cover or the Like"; cibulka, U.S. Pat. No.949974 entitled "Closure for Cans"; U.S. patent No.1433544 to j.c. gibbs entitled "Sifter Can"; l.b. pronsanitz, U.S. patent No.1765284 entitled "Ink Well Closure"; U.S. patent No.1888363 to c.e. tannewitz entitled "Inkwell"; U.S. Pat. No.2492846 to Coyle et al, entitled "Dispensing Container with Slide close"; U.S. Pat. No.4170724 to Waterbury entitled "Vendable recoverable Beverage Container"; U.S. Pat. No.4201320 to Eppenbach entitled "Measuring Dispenser"; U.S. Pat. No.4434906 to Florczyk et al, entitled "Container bathing Opening Means"; lyon, U.S. Pat. No.5025945 entitled "Beverage Container"; U.S. Pat. No.5086941 to English et al, entitled "Dispenser Closure Assembly"; U.S. Pat. No.5462189 to Pierce, entitled "readable, referenceContainer System"; wong U.S. Pat. No.6354454 entitled "Bottle Cap"; and U.S. Pat. No.6439442 to Markert et al entitled "Lid With a Slidable Dispensing Spout". The disclosures of these U.S. patents are incorporated by reference herein in their entirety.

Reclosable beverage lids or containers can be seen in the following patents: U.S. Pat. No.4749099 to Davis et al entitled "drop Preserver"; hambleton et al, U.S. Pat. No.5470817 entitled "Slidable Reclosable Plastic led"; and Waterbury, U.S. Pat. No.4127212 entitled "Vendable reusable content Container," the entire contents of each of which are incorporated herein by reference. In U.S. patent No.4749099, a push-in tab (a push-in tab) is interconnected to a slide plate within a track formed in the metal top of the container. The push tab is operated to tear the scored portion down to the top to reveal an opening whereby the slide panel may be moved over the opening to protect the unused contents of the container interior. In U.S. patent No.5470817, a plastic container lid includes a main lid member and a slide member. The main cover member has support rails between which the slide member is located and which are inclined with respect to the plane of the main cover member to retain the slide member on the cover. A hole is provided on the main cover member, and the slide member may cover the hole. The slide member further includes a portion engageable by a finger. Us patent No.4127212 relates to a reclosable beverage container and provides a slidable cap mounted on the upper end of the container for movement over an opening in the lid. The cap cannot be removed from the lid.

The aforementioned patents are not generally applicable to the disposable lid/cup market where cost, storage, ease of manufacture, etc. are paramount.

For disposable lids, the closure panel is typically incorporated into the upper wall of the plastic lid, defined by a score line, so that the closure panel separates from the adjacent portion of the lid along the score line, and is folded back to open the drinking aperture in the lid; optionally, fixed in its open position on an upwardly projecting lug; and can be folded back over the rim to close the lid. These lids are difficult to work properly and often suffer from severe spillage (particularly for hot beverages), but nevertheless have enjoyed exciting great commercial success in part because they meet the demanding cost criteria of the disposable product market.

Although not reclosable, dome-type cup lids have a more even, displaced lid (displaced flap) with a folding-type closure panel that folds to a considerable extent because they are preferred by consumers and are themselves capable of controlling some spills because they increase the "spill height" of the cup above the contained beverage. Such lids include a dome shape supported by a thermoplastic polymeric material and having an opening for consuming the beverage when the lid is applied to a cup, as is well known in the art. The cap and the opening and closure formed thereon have various shapes.

A Reclosable dome is seen in U.S. Pat. No.6732875 entitled "Reclosable Container Lid" to Smith et al and U.S. Pat. No. D489260 entitled "Reclosable Container Lid" to Smith et al, each of which is incorporated herein by reference in its entirety. The cover includes a cover member and a rotatable disk member mounted in the cover member. A boss (a post) is provided on the periphery of the lid for rotating the disc between open and closed positions beneath the drinking aperture. Obviously, features such as drain holes must be incorporated due to the geometry of the disc/lid and the lid/disc combination requiring redundant lid construction, that is, two layers, over the entire top wall. In addition, the proposed cover feature prevents efficient nesting, increasing storage, packaging, and shipping costs. The disclosed embodiments also may prevent stacking of cups on a lid when a consumer purchases multiple servings of beverage; it also has a negative impact on the prevention of spillage by closing the drinking aperture.

While offering many options, the aforementioned prior disposable lids suffer from one or more of the following disadvantages: difficult to operate and ineffective to reclose; overflow cannot be effectively controlled; the material cost is high; storage, packaging and transportation costs are prohibitive; stacking with cups on lids, etc. As an invention, these deficiencies in the art are overcome and a reclosable lid is provided that is durable and disposable, easy to use, stackable, effective in preventing splashing and spilling, easy to manufacture from thermoplastic materials using existing machinery, and inexpensive.

Disclosure of Invention

The present invention provides a beverage lid for a cup, the beverage lid being made of a polymeric material and comprising: a thermoformed dome member, said dome member comprising: a side wall and a top wall, the top wall having an upper surface and a lower surface, a post aperture, a drinking aperture at a periphery of the top wall and a pair of ramps depending from the lower surface of the top wall, wherein each ramp has a substantially S-shaped profile, the S-shaped profile of the ramp having a substantially vertical portion adjacent an inwardly curved portion adjacent a substantially horizontal portion; and a thermoformed elongated closure plate having opposed engagement edges along its length, an upper surface with lugs projecting upwardly therefrom, and a drinking aperture sealing area. Said dome member and elongated closure plate being configured such that opposed engaging edges on said elongated closure plate are slidably mounted in ramps on the underside of said top wall for reclosably sealing said drinking aperture; said post projecting upwardly through a post aperture in said top wall, said elongated closure plate further characterized in that said post is displaceable generally radially within said slide for movement between a sealing position in which a sealing region of said elongated closure plate seals against said drink aperture and an open position in which said drink aperture is in communication with the interior of the dome member, said elongated closure plate sealing against said post aperture when said elongated closure plate is in the sealing position, said cover being disposable.

The present invention provides a disposable, reclosable cup lid that is thermoformed from a polymeric material and includes a dome member and an elongated closure panel. The thermoformed dome member may have a side wall and a top wall having upper and lower surfaces and a drinking aperture at the periphery of the top wall. The top wall may also define a pair of ramps depending from a lower surface of the top wall and further define a post aperture disposed relative to the drink aperture. The elongated closure panel may have opposed engagement edges, an upper surface with a post projecting upwardly therefrom, and a drink aperture sealing area. When assembled, the dome member and the elongated closure plate may be configured such that the opposed engagement edges of the elongated closure plate are slidably mounted in the ramps for substantially radial displacement. Such lids can be stacked during use to reduce space requirements.

Other features and advantages of the present invention will become apparent from the following discussion and the accompanying drawings.

Drawings

The present invention will hereinafter be described in conjunction with the appended drawings, wherein like designations denote like elements, and wherein:

FIG. 1 is a perspective view of a two-piece reclosable beverage lid for a cup in accordance with the present invention with the closure panel in an open position;

FIG. 2 is a top view of the lid shown in FIG. 1, with the closure panel in an open position;

FIG. 3 is a top view of the lid shown in FIG. 1, with the closure panel in the closed position;

FIG. 4 is a bottom perspective view showing additional details of the lid shown in FIG. 1;

FIG. 5A is a cross-sectional view of the lid of the present invention taken along line 5-5 of FIG. 2, showing the interconnection of the dome member with the elongated closure plate and a cup stacked on the lid;

FIG. 5B is an enlarged detail of the interconnection of the dome member with the elongated closure plate shown in FIG. 5A;

FIG. 6A is an end view of an elongated closure plate;

FIG. 6B is an enlarged detail of an edge of the elongated closure plate shown in FIG. 6A;

FIG. 6C is a cross-sectional view along the centerline of the closure plate showing the profile of the lugs and closure grooves;

FIG. 7 is an enlarged partial cross-sectional view showing details of the ramps and the elongated closure plate on the lid of the present invention;

FIG. 7A is a detail view showing the profile of a slide;

FIG. 8 is a partial cross-sectional view showing the closed ridge around the drinking hole;

FIG. 9 is a side cross-sectional view showing the stacked condition of cups on lids according to the invention and the outline of the lids along the line 9-9 of FIG. 2;

FIG. 10 is a partial cross-sectional view of another alternative interconnection of the dome member with the elongated closure plate, wherein the closure plate is substantially flat except for the posts;

FIG. 11 is a side view showing a nested stacked condition of lids on a lid in accordance with the present invention;

FIG. 12 is a bottom view of an alternative embodiment of the cap of the present invention wherein the dome member has a pair of scallops;

FIG. 13 is the profile of the ramp shown in FIG. 12 at the inward maximum projection;

FIG. 14 is an alternative configuration of a slide on a lid of the present invention having angled corners;

FIG. 15 is a partial profile of the closure plate shown in FIG. 14;

FIG. 16 is a perspective view of another slide plate for coupling with the cover of the present invention, wherein the slide plate has a generally chamfered shape; while

FIG. 17 is a partial end view of the closure plate shown in FIG. 15.

Detailed Description

The following detailed description of the invention is intended for purposes of illustration and example only. Various modifications within the spirit and scope of the invention will become readily apparent to those skilled in the art, as set forth in the appended claims. Terms are given here in their ordinary sense unless a more specific definition is given or otherwise indicated by the context.

"aspect ratio" refers to the ratio of the length of an object to the width of the object, for example the ratio of the length of an elongated closure panel to the width of the same elongated closure panel.

"generally radial" refers to a direction substantially parallel to or substantially along a diameter of the workpiece.

"deformed S-shape" refers to those contours that resemble an S-shape, such as the "5" shape shown in FIG. 7A.

"S-shaped profile" refers to a substantially S-shaped profile configuration as shown in the figures, such as element 176 in FIGS. 5A and 5B. The S-shaped profile, whether deformed or not, is distinguished from the C-shaped profile disclosed in U.S. Pat. No.6824003, the entire contents of which are incorporated herein by reference.

"undercut depth" refers to the distance a groove extends laterally under (or over) a lateral protrusion of the same thermoformed structure to form a lateral groove in the part. The undercut is characterized by a so-called "negative draft" discussed below. If undercut is not experienced, the part or structure will have a "positive draft". When used in conjunction with undercuts having different depths, such as scalloped undercuts, undercut depth refers to the undercut depth at the maximum lateral depth of the undercut.

"scalloped arrangement" means in the form of a series of either rounded elements or angular projections forming a boundary. One non-limiting example of a scalloped arrangement is shown in fig. 12, element 158.

"disposable" means that the object is intended to be discarded after one or at most a few uses.

By "substantially closed" is meant that no or substantially no spillage occurs from the elongated closure panel in the closed position.

In one form, the invention provides a reclosable disposable lid for a cup, the lid being made of a polymeric material and comprising: a) a thermoformed dome member having side walls and a top wall, the top wall having upper and lower surfaces and a drinking aperture at the periphery of the top wall, the top wall further defining a pair of ramps depending from the inner side thereof, the top wall further defining a post aperture disposed inwardly of the drinking aperture; b) a thermoformed elongated closure panel having opposed engagement edges along its length, an upper surface with a post projecting upwardly therefrom, and a drinking aperture sealing area; c) said dome member and elongated closure panel being configured such that opposed engaging edges of the elongated closure panel are slidably mounted in the ramps on the underside of said top wall to resealably seal said drinking aperture; wherein said post projects upwardly through a post aperture in said top wall, said elongated closure plate further characterized in that said post is displaceable in said slide in a generally radial direction to move between a sealing position wherein a sealing area on said closure member seals said drink aperture and an open position wherein said drink aperture is in communication with the interior of the dome member, and further wherein said closure member substantially seals said post aperture when in said sealing position. The runners may substantially span the top wall of the dome member and generally parallel undercut grooves are formed between lower portions of the runners and a lower surface of the top wall. In one suitable form, the grooves may be configured in a scalloped arrangement along the length to form grooves with varying undercut depths.

In another form, the elongate closure plate may be substantially flat and the opposed engaging edges of the elongate closure plate may have substantially the same thickness as the elongate closure plate, with substantially parallel undercut grooves on the runners. In yet another form, the opposed engaging edges of the elongated closure plate each carry thermoformed flanges which are contoured to face-to-face contact with the generally parallel undercut grooves on the runners, at least over a portion of their and corresponding contours of the runners. In this case, the opposed engaging lugs on the elongate closure plate may have a substantially S-shaped profile and the undercut groove on the ramp may have a matching S-shaped profile. Alternatively, the engaging bead on the closure plate or the undercut groove on the ramp may have a substantially S-shaped profile, and this substantially S-shaped profile may be matched to the deformed S-shaped profile of the corresponding undercut groove or engaging bead, so that when the closure plate is mounted in the ramp, the corresponding profiles of the bead and edge are at least over a part of the profile of the mounted closure member in the ramp, forming an air gap between the engaging bead of the closure member and the ramp. If desired, the closure plate may have chamfered longitudinal edges; a suitable angle for the chamfer is about 5 to 15 degrees, or about 8 to 12 degrees.

The undercut groove may have an undercut depth of about 0.05080 to 0.15240 centimeters (0.020 to 0.060 inches); generally, the undercut groove has an undercut depth of at least about 0.06350 centimeters (0.025 inches) and at most about 0.15240 centimeters (0.060 inches).

The reclosable cap of the present invention may further comprise: the elongated closure plate has a length of about 1/2 to 3/4 of a diametrical length of the dome member; the length of the elongated closure plate may be about 2/3 a of the diameter of the dome member; and the elongated closure panel has an area of about 5% to 25% of the area of the top wall. The area of the elongated closure panel is generally no more than about 25% to 35% of the area of the top wall. The elongated closure plate may have an aspect ratio (as defined herein) of at least about 1.5, or at least about 2.0, or at least about 3.

The upper surface of the top wall generally defines a trough with a trough surface and a crown having a height H above the trough surface adjacent thereto, the trough and crown being adapted to receive the base of a cup, thereby enabling stacking of multiple cups with lids on top of each other. To allow stacking, the posts project up from the groove surface by at most about 1.25H and are disposed inwardly relative to the elongate closure member when the elongate closure member is secured in the slideway. In one suitable form, the crown has a top wall with an arcuate upper surface, for example the top wall of the crown may have a radius of curvature of about 0.06350 to 0.254 centimeters (0.025 to 0.1 inches). In one suitable form, the crown has a recessed portion (a gap portion) of lesser height above the groove surface in radial alignment with the drinking aperture, wherein the recessed portion on the crown has an arcuate upper surface. When so disposed, the notched portion typically has a height of about 0.75H to 0.95H above the surface of the groove.

The elongate closure member may be provided with a vent hole arranged such that when the elongate closure member is in the open position, the post hole communicates with the interior of the dome member, thereby venting the interior in the open position to facilitate consumption of the beverage. Alternatively, a vent hole may be provided elsewhere on the lid when venting is desired.

The specific construction of the lid of the present invention includes: a) a one-piece dome member with a sidewall and a top wall, i) said sidewall having a mounting groove in a lower portion thereof, the mounting groove being configured to engage a brim of a cup and form a seal therewith; ii) said top wall also having an upper surface and a lower surface and being formed with a drinking aperture at its periphery, a sealing ridge being formed around said drinking aperture, said top wall further being provided with a pair of generally parallel runners forming generally parallel undercut grooves between the lower surface of said top wall and the lower portion of said runners, said top wall further having a post aperture disposed inboard with respect to the drinking aperture; b) a thermoformed elongated closure plate having an upper surface with a post projecting upwardly therefrom, a sealing groove formed around the sealing region, and opposed engagement edges along its length; c) the dome member and elongated closure plate being configured such that longitudinal engaging edges of the closure plate can be slidably mounted in a slideway on a lower surface of the top wall of the dome member to resealably seal the drinking aperture as the elongated closure plate slides along the slideway; d) wherein when the elongate closure plate is mounted in the ramp, the lug on the elongate closure plate projects upwardly through the post aperture, the post aperture and lug thereby cooperating to limit displacement of the elongate closure plate relative to the dome member; and e) the sealing position of the elongated closure plate is further characterized by the sealing ridge being disposed in a sealing groove on the elongated closure plate around the drinking aperture.

Another specific configuration of the cap of the present invention comprises: a) a thermoformed dome member with a side wall and a top wall, i) said side wall having a mounting groove for removably mounting said lid to a cup, said side wall forming a crown around a recess with a recessed surface on said top wall, said crown having a height H above the recessed surface on said top wall; ii) said top wall having an upper surface and a lower surface and defining a drinking aperture at its periphery, said top wall further having a rail depending from its lower surface, said top wall further having a post aperture disposed inboard with respect to the drinking aperture; b) a thermoformed elongated closure plate having an upper surface with a post projecting upwardly therefrom and a drinking aperture sealing area; c) said dome member and elongated closure plate being configured such that said elongated closure plate is slidably mounted for generally radial displacement in longitudinal tracks on the lower surface of said top wall for reclosably sealing the drink aperture with a drink aperture sealing area thereon, wherein said post projects upwardly through the post aperture in the top wall; d) said post apertures and studs thereby cooperating to limit radial displacement of said elongated closure plate relative to the dome member, and e) wherein said studs project upwardly from the surface of the recess by a height of at most about 1.25H, such that when a plurality of beverage lids of the type defined by a) -e) are nested within one another, the stacking operation of the lids is substantially unaffected by said studs.

In one form, the lid of the present invention is made by a thermoforming process. Generally, a thermoforming process refers to pressing and/or stretching a heated deformable material into a final shape. In its most fundamental aspect, the thermoforming process involves wrapping a softened sheet over a forming mold. In more detailed aspects, the thermoforming process is the automated high speed positioning of a heated sheet with precisely controlled temperature in a pneumatic forming station, whereby the shape of the workpiece is formed using a die, followed by trimming and regrinding as is well known in the art. Other forming techniques besides conventional hot forming processes are also suitable for making the workpieces described in the present invention. These forming processes are varied, such as pre-softening the calendered sheet to a temperature below the final melting temperature, cutting flat sections (i.e., blanks) from the sheet, transferring the blanks to a mating die using gravity or mechanical means, thereby forming the blanks into a workpiece using heat and pressure. Other alternatives include using cover, vacuum, pressure, moldless manual blowing, matched die cutting, tumble cover (billow flap), vacuum snap back (vacuum snap back), tumble vacuum (billow vacuum), plug assist vacuum (plug assist vacuum), reverse draw with plug assist, pressure bubble immersion (pressure bubble immersion), trapped sheet, slip, diaphragm, double-cut sheet (twin-cut sheet), double sheet roll forming, and suitable combinations of the foregoing. Detailed description is given in book "thermo forming" by j.l. throne published by Coulthard in 1987. Pages 21 to 29 of this book are incorporated by reference into the present invention. Suitable alternatives also include a pillow forming technique that creates positive air pressure between two softened sheets to cause them to expand against a clamped male/female mould system to form a hollow article. The metal mold is etched with a fine to coarse pattern to simulate a natural or grain-like texture look. Suitably shaped workpieces may be trimmed in-line using a cutting die to optionally reuse the trimmed product. Other solutions for increasing productivity include simultaneously forming multiple workpieces with multiple areas to maximize throughput and minimize scrap.

Thermoplastic materials are intended to include those suitable for thermoplastic molding dome hot cup lids. One suitable material for the lid is a styrene polymer, which may be filled or unfilled. Such compounds may have sufficient pigment to provide opacity or near opacity. Other suitable materials include polyolefins such as polyethylene, polypropylene and mixtures thereof, polyesters, polyamides, polyacrylates, polysulfones, polyether ketones, polycarbonates, acrylics, polyphenylene sulfides, acetyl, cellulose, polyetherimides, polyphenylene ether/polyphenylene oxide, styrene-maleic anhydride copolymers, styrene-vinyl cyanide copolymers, polyvinyl chloride, and engineering resin derivatives thereof. These materials may be similarly filled or unfilled. The filler for any polymeric material may be any conventional material, as is well known to those skilled in the art or to those of ordinary skill in the art.

The lid may be thermoformed from a sheet of thermoplastic material. Typically, the thermoplastic sheet from which the lid is made to have a thickness of about 10 to 20 mils (thousandths of an inch), or a panel thickness of about 14 to 19 mils. The sheet from which the blanks have been cut can be made of regrind material and can be recycled. Also, the sheet from which the blank has been cut may be made from a stock material. Also, sheets of blanks that have been cut out can be prepared from a mixture of raw and regrind material.

The thermoformed workpiece must be designed to allow the mold sections to be freely separated from the molded workpiece without undue interference with the surface of the workpiece. The surface of such a workpiece typically includes a so-called positive "draft" relative to the direction of movement of the mold during separation to ensure that little or no interference occurs between the molded workpiece and the inner surface of the mold sections during separation. The interference between the workpiece and the die is commonly referred to as "negative draft". The draft can be viewed as the difference between the upper and lower transverse spans of the mold cavity. Positive draft allows the mold to be cleanly pulled from the mold; however, the undercut itself has a negative draft angle.

In the present invention, the undercut depth and the distance required to secure the closure plate to the domed portion of the lid are generally minimized in order to reduce the manufacturing difficulties that may be associated with negative draft. In particular, the runners may have undercut grooves formed by their inner walls and positively draft outer walls, wherein the outer walls of the runners have an arcuate profile.

Referring now to fig. 1-11, there is shown a reclosable thermoformed beverage lid 10 for a cup 100, which is constructed in accordance with the present invention (including variations of the various features). The lid of the present invention comprises a thermoformed dome 12 and an elongated closure plate 70, the elongated closure plate 70 being mounted beneath the dome 12 as will be further explained.

Dome member 12 includes a circumferential side wall 14 depending from a disc-shaped top wall 16. The side walls 14 and top wall 16 of dome member 12 define an inboard dome cavity 18. The top wall 16 also includes an inner surface 20 and an outer surface 22 opposite the inner surface 20 when viewed from the inside dome pocket 18. As will be apparent from viewing the drawings, the top wall 16 is recessed relative to the side walls 14 because the upper ends of the side walls 14 form a crown 24. The crown 24 is rounded at its top end to enhance the ergonomic design of the dome member 12 and to make it more comfortable when in contact with the user's lips. For example, a radius R1 of up to about 0.12700 centimeters (0.050 inches) may be used for the crown 24. The height of the crown 24, i.e., the distance the crown extends above the outer surface 22 of the dome member 12, is labeled H. Additional details of the crown 24 will be described below in connection with other features of the cap 10.

The side wall 14 also includes a generally annular skirt 26 depending therefrom. The skirt 26 includes an annular sealing groove 28 formed adjacent the distal end of the side wall 14, and a generally annular flared rim 30 (an annular flared trim) depending from the annular sealing groove 28. Annular sealing groove 28 is configured to mate with and form a seal with brim 104 of cup 100, as is known in the art and shown by reference in fig. 10. Thus, the annular sealing groove 28 provides a means for preventing the contents from leaking out of the cup 100 when the lid 10 is secured to the cup 100. The flared rim 30, which is generally circular in shape, provides a gripping surface for a user to remove or apply the lid 10 to the cup 100.

The side wall 14 also includes a stacking slot 32 formed in the side wall 14 and the crown 24. The stacking slot 32 facilitates stacking of individual lids 10 on top of each other and prevents the lids 10 from sticking together when not stacked. For each lid 10, four stacking slots 32 are shown; this number is not critical and may vary depending on manufacturing needs or end use. An example of a stacked state of the cover on the cover is shown in fig. 11.

A lip groove 34 is also formed in a portion of the side wall 14 to visually guide the user to the drinking aperture 38 in the lid 10 and to provide a more comfortable, thinner drinking surface on the side wall 14. The lip recess 34 is shown shaped to receive the consumer's lower lip. Specifically, the lip recesses 34 are defined by edges 36 of the lip recesses 34. In one particular form, the rim 36 has a generally straight base 36a, with the base 36a being connected at each end to a generally outwardly curved end 36 b. Lip recesses 34 are disposed radially inward from the surface of the sidewall 14. Although the lip recesses 34 are shown on the crown 24 and the side walls 14, the lip recesses 34 may be limited to the crown 24 or the side walls 14. Also, the height H of the crown 24 is reduced at the location of the lip recess 34 to facilitate drinking from the cap 10 without interference from the crown 24. The shape and configuration of the lip recesses 34 may be varied to conform to a number of design parameters. Similarly, the degree of the grooves 34 and the crown height H therein may vary. The crown portion may have a recessed portion 34a having a small height H' at the lip groove 34.

The top wall 16 includes a drink aperture 38 and also includes a post aperture 40. The drinking aperture 38 is disposed adjacent the crown 24 and, in particular, may be disposed within an area defined by the lip recess 34. The post aperture 40 is located substantially centrally in the top wall 16 and radially inward relative to the drink aperture 38. More specifically, the post apertures 40 are radially aligned with the drink apertures 38. A raised sealing ridge 42 surrounds the drinking aperture 38 and corresponds in shape to the drinking aperture 38, but has a greater overall length than the drinking aperture 38. By way of example, the drinking aperture 38 may have a width of about 0.111252 centimeters (0.0438 inches) and a length of about 0.63500 centimeters (0.250 inches), wherein the length corresponds to the diameter of the top wall 16. The sealing ridge 42 is configured to project toward the inboard dome bowl 18 a distance of about 0.1016 cm (0.04 inch) and has an arcuate radius of about 0.1016 cm (0.04 inch).

The post aperture 40 is substantially rectangular and forms a "CLOSE" (CLOSE) stop limit edge 44 and an "OPEN" (OPEN) stop limit edge 46 in a direction toward and away from the drink aperture 38, respectively. The close stop limit edge 44 may be approximately 3.00990 centimeters (1.185 inches) from the drink aperture 38 and the overall length of the stake hole 40 may be approximately 1.72212 centimeters (0.678 inches). The center of the drink aperture 38 and each of the post apertures 40 are die cut or stamped during the manufacture of the lid 10 as is known in the art.

A pair of runners 48 are formed on the inner surface 20 of the top wall 16 so as to span substantially the entire diameter of the top wall 16 in the direction of the drink aperture 38 and the post aperture 40. The runners 48 depend from the inner surface 20 of the top wall 16 and a corresponding longitudinal undercut groove 62 is formed in each of the runners 48 and the inner surface 20 of the top wall 16, respectively. As described below, the ramps 48 present different contours when viewed from either the inner surface 20 or the outer surface 22 of the top wall 16.

The runners 48 are positioned to straddle the aligned drink aperture 36 and post apertures 40 a distance sufficient to form a plateau region 50 between the drink aperture 36 and post apertures 40 when viewed from the outer surface 22 of the top wall 16. The land area 50 is distinguishable from the remainder of the top wall 16 and is therefore adapted to receive indicia or the like thereon. The ramp 48 is formed such that the substantially flat outer surface 22 includes a smooth arcuate transition surface 52 at the ramp outer wall terminating in a flat bottom surface 54, the flat bottom surface 54 having a channel 56 opposite the transition surface 52. The channel 56 is bounded by a substantially vertical wall 58 terminating at the plateau region 50 on the top wall 16. Thus, when viewed from the outer surface 22, the ramps 48 are rolled under longitudinal undercut edges on a land area 50 in the top wall 16.

The channel 56 forms a gripping surface or overhang 60, when viewed from the dome bowl 18, adapted to receive an elongated closure plate 70 and form an undercut groove 62 between the gripping surface 60 and the inner surface 20 of the land area 50. The arcuate transition surface 52 has a radius of curvature of about 0.6350 centimeters (0.25 inches) and forms an angle of about 45 degrees with respect to the flat bottom surface 54. The flat bottom surface 54 may have a width along the length of each runner 48 of about 0.15748 centimeters (0.062 inches). The inside radius of curvature of the passageway 56 may be approximately 0.10922 centimeters (0.043 inches). The undercut groove 62 has an undercut depth of about 0.0508 to 0.0762 centimeters (0.02 to 0.03 inches), and more specifically, a depth of about 0.06350 centimeters (0.025 inches).

The undercut depth 65 is the distance from the outermost projection of the portion 60 to the bottom of the groove 62, as shown at 59 in fig. 7A.

The runners 48 are formed in the top wall 16 in a manner that permits the molding material to deform into a retaining area of the runners 48 and minimizes thinning of the thermoplastic material. To prevent the opposite end of the runners 48 from being thinner than desired, a vacuum slit may be provided in the mold that mitigates thinning at the sharp corners of the ends of the runners 48. Optionally, a larger radius may be machined at the corner, which will form an ellipse.

The second feature on the lid 10 is an elongate closure plate 70. The elongated closure plate 70 is an elongated rectangular member having an upper surface 72, a lower surface 74, opposed longitudinal engaging edges 76 (see fig. 6B) and opposed ends, including a closed end 78 and a non-closed end 80. A post 82 projects from the upper surface 72 of the elongated closure plate 70 at a distance from the sealing area 84. A sealing area 84 is formed at the closed end 78 of the elongated closure panel 70 and includes a groove 86, the groove 86 corresponding in shape and size to the drinking hole sealing ridge 42 on the top wall 16. The opposed longitudinal edges 76 of the elongated closure panel 70 are formed with a unique engagement profile (fig. 5A, 5B, 6A, 6B and 7) or, optionally, as substantially flat ends of the flat elongated closure panel 70 (fig. 10).

With particular reference to fig. 5A and 5B, the opposing longitudinal edges 76 each have a substantially letter "S" shape, with one side inverted relative to the opposite shape. Each of the opposed longitudinal edges 76 includes an upper outwardly projecting inset lip 88 that transitions to a lower inwardly arching engagement portion 90. Insertion lip 88 is sized to fit within undercut groove 62 on dome member 12. Also, the insertion lip 88 is sized to be slidingly received within the undercut groove 62 so as to achieve a slight friction therebetween, but preferably is not exactly the same shape as the undercut groove 62, thereby avoiding suction or excessive friction between the undercut groove 62 and the insertion lip 88 that would otherwise inhibit sliding movement. In this regard, it is preferred that a slight gap 63 be formed between the closure plate and the undercut groove 62, as shown in FIG. 7. The underside inwardly domed engagement portion 90 is shaped to at least partially surround the corresponding gripping surface 60 of the ramp 48. By at least partially surrounding the gripping surface 60 with the arcuate engagement portion 90, improved leakage prevention is achieved when the cup 100 topples or topples over with the lid 10 secured thereto, and/or heat is maintained within the cup 100 when the lid 10 is applied. This is because the surface area is increased compared to known lids and therefore the surface contact between the domed portion 12 and the elongate closure plate 70 is enhanced.

The closure plate 70 is sized to correspond to the dimensions of the chute 48 so as to form a substantially fluid-tight fit therebetween, yet still allow the elongated closure plate 70 to slide within the chute 48. Thus, the insertion lip 88 may have an inner diameter of about 0.02540 centimeters (0.010 inches), the outwardly arched engagement portion may have an outer diameter of about 0.14478 centimeters (0.057 inches), and the distance between the insertion lip 88 and the inner surface of the arched engagement portion 90 may be about 0.15240 centimeters (0.060 inches) when viewed from the inner surface of the elongated closure plate 70.

The opposed closed ends 78 and non-closed ends 80 may be formed with identical outwardly arched insert lips 88 that transition to an underside inwardly arched engaging portion 90, or alternatively, terminate in the same plane as the upper surface 72 of the elongated closure panel 70. Where both ends 78, 80 are formed with an outwardly arched inset lip 88 and an underside inwardly arched engagement portion 90, the forming operation may be continued around the elongated closure panel 70 or interrupted at one or more corners of the elongated closure panel 70.

The elongated closure plate 70 also includes a vent hole 92 formed therein. A vent hole 92 may be located between the sealing area 84 and the post 82 such that the vent hole 92 is revealed when the drink aperture 38 is opened. The vent hole 92 is adapted to ensure continuous flow of the container contents through the drinking aperture 38 while venting the container interior. Alternatively, the vent 92 may be provided elsewhere on the lid 10. In addition, the post 82 and the sealing area 84 are spaced apart by a distance defined by the drink aperture 38 and the stop limiting edge 44 on the post aperture 40.

As can be seen in the drawings, the length of the elongated closure plate 70 is approximately one half to three quarters of the length of the diameter of the top wall 16. The length of the elongated closure panel may be approximately two thirds of the length of the diameter of the top wall 16. In other words, the area of the elongated closure panel may be about 5% to 25% of the area of the top wall 16, or about 10% to 45% but not more than 50% of the area of the top wall 16.

It is noted that the elongated closure plate 70 has an aspect ratio (L/W, fig. 4) of at least about 1.5, at least about 2, or at least about 3.

In fig. 9, a stack of cups on a lid is shown that would be easily achieved with the lid 10 of the present invention. The cup 100 includes a bottom end 102, an upper rim 104, and a sidewall 106 connecting the bottom end 102 to the rim 104. The bottom end 102 includes an annular support surface 108 and a cup bottom 110 recessed within the annular support surface 108 to define a wall height 112 between the annular support surface 108 and the cup bottom 110. Bounded by the annular support surface 108, the cup bottom 110, and the wall height 112, an open area 114 is defined. Such a configuration of the cup bottom end 102 is well known in the art. The annular support surface 108 rests on the cap 10 against and/or within the crown 24, while the post 82 easily fits within the opening area 114. Thus, in combination with the two-piece lid 10, stacking of the cups on the lid is accomplished in a manner not previously possible without interference from the studs 82.

As will be seen from fig. 5A, the height H' of the post 82 may be only slightly higher above the surface 22 than the height H of the crown 24. This feature allows for stacking of cups on lids as previously described and lid-to-lid stacking as discussed below.

During operation, such as at the assembly site and prior to use, the formed longitudinal edge 76 on the elongated closure panel 70 is fitted by the user into sliding engagement with the longitudinal undercut groove 62 and the gripping surface 60. Upon assembly, the studs 82 protrude through the stud holes 40 and the drink apertures 38 are opened or closed depending on the position of the elongated closure plate 70. In use by the consumer, the post 82 is able to slide inside the post hole 40 between the opening stop limiting edge 46 and the closing stop limiting edge 44 to open or close the drink hole 38, respectively. Urging the lug 82 to close the stop limiting edge 44 (toward the drink aperture 38) urges the sealing ridge 42 on the top wall 16 into engagement with the groove 86 on the elongated closure plate 70 urging a snap closure therebetween. Pushing the post 82 to the open stop limit edge 46 (away from the drink aperture 38) will disengage the sealing ridge 42 from the groove 86, releasing the snap closure between these components. The stop limiting edges 44 and 46 will limit the movement of the studs 82 and thereby bring the elongated closure plate 70 into a position that fully closes and fully opens the drinking aperture. It can be anywhere between the outermost boundaries of the movement and will be maintained because of the slight friction between the longitudinal edge shape of the elongated closure panel 70 and the configuration of the chute 50 on the top wall 16.

The sealing area 84 of the elongated closure panel 70, including the recess 86, does not protrude through the drinking aperture 38, but instead forms a surface area 94 within the recess 86 and covering a greater area than the drinking aperture 38. Because the elongated closure panel 70 has a surface area 94 that completely covers the drinking aperture 38 from the inner surface 20 of the top wall 16, inversion or tipping of the lidded and closed container will cause the contents of the container to further force the elongated closure panel 70 and thereby press the surface 94 against the drinking aperture 38. Thus, since the drinking hole 38 is sealed from the inside of the lid 10, leakage will be prevented better than closing from the upper surface of the lid 10, thereby enhancing the sealing effect on the container contents.

Although closure plates with formed edges are preferred, substantially flat closure plates with flat engagement edges 76 will work equally well, as schematically illustrated in fig. 10. Fig. 10 is a cross-sectional view similar to fig. 5A.

The crown 24 on the side wall 14 is dedicated to preventing stacked cups 100 from sliding off the lid 10. In particular, the crown 24 has a height and size such that the bottom end 102 of the cup 100 will fit against the inner wall surface 25 of the crown 24. Also, the height H of the crown 24 substantially corresponds to the height of the post 82, and since the post 82 is remote from the crown 24, the stacking operation of the cup 100 with the lid 10 is not affected by the post 82, as the post 82 will fit within the open area 114 on existing containers and cups when stacking.

Referring to fig. 11, it is shown that the lids 10, 110, 120 of the present invention can be easily stacked in a nested stack 125 at a pitch 130 of about 0.45720 centimeters (0.180 inches) because the posts do not protrude significantly above the crown 24.

Although the drink aperture 38, the sealing ridge 42, and the groove 86 are illustrated as being generally oval-shaped, it will be appreciated that any suitable shape will achieve the intended function of sealing the drink aperture 38, so long as the sealing ridge 420 and the groove 86 correspond in shape and size to form a snap-fit therebetween. For example, alternative shapes for the drink aperture 38 may include, but are not limited to, round, square, or rectangular.

Although described separately, dome member 12, sidewall 14, and skirt 26 are adapted to be made as one piece in a thermoforming process. To illustrate the features of the present invention, various features have been described in connection with the formation of individual lids; however, it will be appreciated by those skilled in the art that known manufacturing methods can be used to simultaneously form a plurality of lids from a single sheet of thermoplastic material.

In general, the lid 10 has a wall thickness of about 10 to 20 mils, or about 14 to 18 mils.

The elongated closure panel 70 may be made from the same material used to form the remainder of the lid 10. However, the elongated closure plate 70 may be made of other lightweight materials.

Referring to fig. 12 and 13, there is shown another cover 150 constructed in accordance with the present invention. The lid 150 has a closure plate 152 generally as described above, and the dome 154 carries a pair of opposed ramps 156, 158. The runners 156 and 158 have undercut grooves as described in connection with the embodiment shown in FIG. 1; however, the ramps may have a scalloped geometry along the length as shown in fig. 12. The scallop shape facilitates ejection of the product from the mold and may have a radius of curvature of about 0.6350 centimeters (0.25 inches). The scalloped geometry also facilitates deeper undercut grooves as shown in fig. 13, which 13 shows a portion of the profile of the dome along line 13-13, which is an inward projection of increased area.

As can be seen in fig. 13, the undercut groove 160 has an undercut depth 162 of about 45 to 40 mils; the maximum depth and the smaller depth are arranged intermittently.

Alternative configurations for the closure plate on the lid of the present invention may also be used. For example, the plate 170 shown in fig. 14 may be employed within the runners 156, 158 shown in fig. 12. The plate 170 is similar to the closing plate shown in fig. 1; however, the plate 170 has a plurality of angled corners 172, 174, 176, 178 and generally square ends. Also, as shown in FIG. 15, the edge may be provided with a deeper undercut. In fig. 15, the longitudinal edge 180 of the plate 170 is provided with an undercut depth 182 of about 40 mils.

Referring to fig. 16 and 17, there is shown another closure plate 190 which is generally similar to the closure plates previously described except that the plate 190 has beveled edges 192, 194 which may be better seen by reference to fig. 17, fig. 17 being a partial end view of the plate 190.

The plate 190 has an upper medial surface 196 that changes direction downward at a chamfer angle 198, which chamfer angle 198 may be any suitable angle, such as about 10 degrees.

While the invention has been described in conjunction with a number of features, those skilled in the art will be readily able to modify these examples without departing from the spirit and scope of the invention. In view of the foregoing discussion, the relevant knowledge in the art, and the references discussed above in connection with the background and the detailed description section, the disclosure of which is incorporated by reference herein in its entirety, it is considered unnecessary to describe this further disclosure.

Claims (25)

1. A beverage lid for a cup, the beverage lid being made of a polymeric material and comprising:

a) a thermoformed dome member, said dome member comprising:

a side wall and a top wall, the top wall having an upper surface and a lower surface,

the hole of the column is provided with a hole,

a drinking aperture at the periphery of the top wall, an

A pair of ramps depending from the lower surface of the top wall, wherein each ramp has a substantially S-shaped profile with a substantially vertical portion adjacent an inwardly curved portion adjacent a substantially horizontal portion; and

b) a thermoformed elongated closure plate having opposed engagement edges along its length, an upper surface with lugs projecting upwardly therefrom, and a drinking aperture sealing area; wherein:

said dome member and elongated closure plate being configured such that opposed engaging edges on said elongated closure plate are slidably mounted in ramps on the underside of said top wall for reclosably sealing said drinking aperture;

the post projects upwardly through a post aperture in the top wall,

the elongated closure plate is further characterized in that the posts are generally radially displaceable in the ramps to move between a sealing position in which the sealing area of the elongated closure plate seals against the drink aperture and an open position in which the drink aperture is in communication with the interior of the dome member,

the elongated closure plate seals against the post aperture when the elongated closure plate is in the sealing position,

the cap is disposable.

2. The lid of claim 1, wherein the chute substantially spans the top wall of the dome member.

3. The lid of claim 1, wherein the runners include generally parallel undercut grooves formed between lower portions of the runners and a lower surface of the top wall.

4. The lid as in claim 3, wherein the undercut grooves are configured in a scalloped arrangement along their longitudinal direction to define grooves with varying undercut depths.

5. The lid of claim 3, wherein the elongated closure plate is substantially flat and opposing engagement edges of the elongated closure plate have substantially the same thickness as the elongated closure plate and engage with substantially parallel undercut grooves in the chute.

6. A lid according to claim 3, wherein the opposed engaging edges of the elongate closure plate are each provided with a thermoformed collar profiled to engage the undercut groove in surface-to-surface contact over at least a portion of their respective profile with the generally parallel undercut groove of the slide.

7. The lid as in claim 6, wherein the opposed engaging ledges of the elongated closure plate have a substantially S-shaped profile and the S-shaped profile of the opposed engaging ledges of the elongated closure plate matches the S-shaped profile of the chute.

8. A lid according to claim 6, wherein an air gap is defined between the engaging ledge of the elongate closure plate and the substantially S-shaped profile of the ramp when the elongate closure plate is mounted in the ramp.

9. A closure according to claim 3, wherein said opposed engagement edges of said elongate closure plate are chamfered longitudinal edges.

10. The lid of claim 9, wherein the beveled longitudinal edge defines a beveled angle of 5 to 15 degrees with respect to the upper surface of the elongated closure plate.

11. The lid of claim 3, wherein said undercut groove has an undercut depth of 0.0508 cm to 0.1524 cm.

12. The lid of claim 1, wherein the length of the elongated closure plate is 1/2-3/4 of the diameter length of the dome member.

13. The lid as in claim 1, wherein the elongated closure panel has an area that is 5% to 25% of the area of the top wall.

14. The lid as in claim 1, wherein the elongated closure panel has an area that is no more than 30% of the area of the top wall.

15. The lid as in claim 1, wherein the elongated closure plate has an aspect ratio of at least 1.5.

16. The lid as in claim 1, wherein the elongated closure plate has an aspect ratio of at least 3.

17. The lid of claim 1, wherein the chute has an undercut groove formed by its inner wall and a positive draft outer wall.

18. The cover of claim 17, wherein the outer wall of the slide has an arcuate profile.

19. The lid of claim 1, wherein the upper surface of the top wall defines a trough with a trough surface and a crown, the crown having a height H above the trough surface adjacent thereto, the trough and crown being adapted to receive the base of a cup, thereby enabling a plurality of cups with lids to be securely stacked upon one another.

20. The closure of claim 19 wherein said crown portion has a top wall with an arcuate upper surface.

21. The cap of claim 20, wherein the top wall of the crown has a radius of curvature of 0.06350 centimeters to 0.254 centimeters.

22. The closure as in claim 19 wherein said crown portion has a recessed portion of lesser height above the surface of the groove in radial alignment with said drinking aperture.

23. The cap of claim 22, wherein the recessed portion of the crown has an arcuate upper surface.

24. The lid of claim 22, wherein the notched portion has a height of 0.75H to 0.95H above the groove surface.

25. A lid as claimed in claim 1, wherein said elongate closure plate is provided with a vent aperture positioned such that when said elongate closure plate is in an open position, said post aperture is in communication with the interior of the dome member, thereby venting said interior in the open position to facilitate consumption of the beverage.